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Test NTC-3A: Checking Pcm Power & Ground Circuits

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION . For component location and wiring diagram, see WIRING DIAGRAMS article.
  1. Turn ignition off. Disconnect Powertrain Control Module (PCM) Black connector. Inspect connector and terminals for damage. Repair connector and terminals as necessary and perform TEST VER-2A: ROAD TEST VERIFICATION . If connector and terminals are okay, go to next step.
  2. Using scan tool in ohmmeter mode, check resistance of PCM Black connector terminal No. 31, ground circuit (Black wire on AN and DN bodies; Black/Tan wire on all other bodies). If resistance is 5 ohms or more, repair open ground circuit and perform TEST VER-2A: ROAD TEST VERIFICATION . If resistance is less than 5 ohms, go to next step.
  3. Using scan tool in ohmmeter mode, check resistance of PCM Black connector terminal No. 32, ground circuit (Black wire on AN and DN bodies; Black/Tan wire on all other bodies). If resistance is 5 ohms or more, repair open ground circuit and perform TEST VER-2A: ROAD TEST VERIFICATION . If resistance is less than 5 ohms, go to next step.
  4. Using scan tool in voltmeter mode, check voltage on of PCM Black connector, fused B+ circuit (Dark Green/Yellow wire on XJ body; Red/Yellow wire on ZJ body; Red/White wire on all other bodies). If voltage is 10 volts or less, repair open B+ circuit and perform TEST VER-2A: ROAD TEST VERIFICATION . If voltage is more than 10 volts, go to next step.
  5. Turn ignition on. Check voltage on PCM Black connector, ignition switch output circuit. See IGNITION SWITCH OUTPUT CIRCUIT IDENTIFICATION  table. If voltage is 10 volts or less, repair open ignition switch output circuit and perform TEST VER-2A: ROAD TEST VERIFICATION . If voltage is more than 10 volts, go to next step.
    IGNITION SWITCH OUTPUT CIRCUIT IDENTIFICATION

    Application Wire Color
    AB, AN, BE/BR & DN Bodies Light Green/Black
    TJ Body Red/Light Green
    XJ Body Dark Blue/White
    ZJ Body Orange
  6. Turn ignition off. Reconnect PCM connector. PCM ground and power circuits are operating properly. Test passed.
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